Shuttlecock



March 24,1953 w, c. CA LTO 2,632,647

SHUTTLECOCK Filed Feb. 28. 1952 i In uentor Attorney Patented Mar. 24,1953 SHUTTLECOCK William Charles Carlton, Hornchurch, EnglandApplication February 28, 1952, Serial No. 273,819 In Great Britain March12, 1951 3 Claims. (Cl. 273106) This invention relates to the skirts ofshuttlecocks of the type that are usually made in one piece. The objectof the invention is to prevent some deflection of the skirt when theshuttlecock is travelling through the air at high speed.

Deflection of the skirt can be caused by impact with the racket and bythe passage of air, and this invention is devoted to reducing thedeflection caused by the passage of air.

A shuttlecock being cone-shaped, in the types hitherto known, thetendency of the air has been to collapse the shuttlecock skirt whilsttravelling forward at high speed.

The object of this invention is achieved by incorporating in the skirtof the shuttlecock at least one but preferably a number of air foilswhich will tend to expand the skirt of the shuttlecock because of thepassage of air as distinct from causing it to collapse.

In practice this is achieved by making up the skirt of a shuttlecockcomprising a plurality of rearwardly diverging lengthwise extendingstems and a plurality of circumferentially extending ribs disposedoutwardly of the stems whereby there is formed a series of steps ofmaterial with air spaces between them and using the step as the materialspace for necessary strength.

The material in the step is not of constant thickness and the use of anair foil section enables an increased effect to be obtained becausealthough the air at some little way from the shuttlecock is travellingparallel to the direction of flight, near the shuttlecock skirt it istravelling at an angle between that of parallel to the direction offlight and parallel to the angle of the cone so that the air will swoopover these tiny air foils and cause the cone to be expanded.

To enable the invention to be clearly understood an example will now bedescribed with reference to the accompanying drawings in which Fig. 1 isa top plan of a shuttlecock in accordance with this invention as itwould appear in horizontal flight.

Fig. 2 is a front elevation of the shuttlecock shown in Fig. 1. V

ribs.

- Closely examining Figure 3, the direction of flight of the shuttlecockis indicated by thev arrow Y, with the leading edge'of the ribdesignated 5, the trailing edge 6, the outer surface I and the innersurface 8. The angle (1)) is the angle between the outer surface I andthe direction of flight of the shuttlecock while the angle (a) is theangle between the interior conical surface of the shuttlecock and thedirection of flight.

The air on passing over the air foil will tend to cause a force in thedirection of the arrow X and this reduces the tendency of the skirt tocollapse.

To get the tool machined properly to permit this series of steps it isnecessary that the rims should be machined with their leading edge inthe female tool.

It will be understood that the specific air foil shape shown in Figure 3is not essential, the main essential being that a series of steps on theoutside surface of the shuttlecock with air spaces between them shouldbe formed so that air thrown off one step is forced against another fromthe outside surface of one step to the inside surface of the next oneastern of it and that, of course, the ribs should be integral with thestems.

I claim:

1. A shuttlecock comprising a cap and a one piece skirt including stemswhich are thicker than other parts of the skirt and characterised inthat the stems have integral with them at least one rib, the outsidesurface of which is at a smaller angle than the interior conical surfaceof the skirt to the direction of flight of the shuttlecock.

2. A shuttlecock as'in claim 1 in which there are a number of ribs sosited that air passing over the top surface of one will strike theundersurface of the next succeeding rib.

3. A shuttlecock as in claim 1 in which the outside surface of the ribis disposed outwardly from the outside surfaces of the stems.

WILLIAM CHARLES CARLTON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS

